Simultaneous Determination of Cadmium and Lead Using PEDOT/PSS Modified Glassy Carbon Electrode

Sukeri Anandhakumar, Jayaraman Mathiyarasu, Kanala Lakshmi Narasimha Phani, Venkataraman Yegnaraman

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DOI: 10.4236/ajac.2011.24056                

Abstract

In this work, we report the simultaneous determination of cadmium and lead using glassy carbon electrodes (GCE) modified by poly(3,4-ethylenedioxythiophene) (PEDOT) for linear sweep anodic stripping voltammetry (LSASV). The modification allows metal detection without involving oxygen removal, mechanical stirring and introduction of alloying additions such as Hg, Bi, Sb, etc. during the pre-concentration step. Introduction of poly (4-styrenesulphonate) (PSS) as dopant in the PEDOT matrix improves reproducibility, stability and sensitivity in the detection. Both cadmium and lead peaks were readily quantifiable over the linear range of 2 - 10 ?g/ml and the detection limit being 1.47 ?g/ml and 1.15 ?g/ml respectively. The calibration plot shows a linear response with correlation coefficient of 0.9911 and 0.9944 for cadmium and lead respectively. Thus, the GC/PEDOT/PSS modified electrode suggested as a suitable matrix for rapid monitoring of these heavy metals at trace levels.

Keywords

Stripping Voltammetry, Cadmium, Lead, Conducting Polymer, PEDOT-PSS, Heavy Metals

Conflicts of Interest

The authors declare no conflicts of interest.

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